Stringed musical instrument



Aug. 2, 1949. E. F. STROMBERG STRINGED MUSICAL INSTRUMENT Filed May 31, 1946 Patented Aug. 2, 1949 UNITED STATES PATENT OFFICE 2,478,136 STRINGED MUSICAL INSTRUMENT Elmer F. Stromberg', Cambridge, Mass.

Application May 31, 1946, Serial No. 673,242

My present invention relates to stringed musical instruments and particularly to adjustable means built into the neck structure for such instruments to apply' corrective stresses substantially at and towards opposite ends of the neck thereby to straighten the neck should it become bowed by string tension.

The bowing of the necks of stringed instruments is a common occurrence and is obviously objectionable in that it makes it impossible to play the instrument accurately. This result is due to the fact that as the strings are depressed by the fingers of the player against the bowed finger board, the tautness of the strings varies appreciably as compared to an unbowed neck in which the strings and the finger board are in parallel.

In accordance with my invention, I provide a neck structure having a longitudinal channel extending from adjacent its body attaching end forwardly into the head which isangularly disposed with respect to the neck and which is provided with rotatable pegs by which the strings are tensioned. Extensible means in the channel are operative to apply a corrective stress substantially at and towards the opposite ends of theneck.

My extensible meansincludes a rotatable mem her and preferably the rotatable member is located in the neck closely adjacent the junction 'of the head and the neck. 'Ilhe finger board has an opening permitting access to the rotatable member, but otherwise it conceals the channel and the extensible means. In accordance with my invention, the finger board opening is established by terminating it short of the finishing layer on the head thereby to establish a slot to receive the string nut or support which constitutes a closure for the opening and which is tightly held in place when the instrument is strung.

Preferably, my extensible means comprises a rod having one end downturned so that it may be easily anchored in the channel adjacent its body attaching end. The other end of the rod is threaded and extends into the head and is slightly downturned as required by the angular relation between the neck and the head. I mount a member in the channel which establishes a transverse shoulder adjacent the junction of the head and the neck through which the threaded end of the rod freely extends. Threaded on the rod on the neck side of the shoulder and in engagement with the shoulder is a nut which, when rotated, causes stress to be exerted adja- 4 Claims. (01. 84-4293) cent to and towards the opposite ends of the neck thereby to correct any bowing of the neck due to string tension.

In the accompanying drawings,.I have shown an illustrative embodiment of my invention from which its several novel features and advantages will be readily apparent.

In the drawings:

Fig. 1 is a fragmentary and partly broken away view of an'instrument of the guitar type in accordance with my invention.

Fig. 2 is a section along the lines 2-2 of Fig. 1, and

Fig.- 3 is a section along the lines 33 of Fig. 2 on an enlarged scale with a part of the string nut broken away.

In the drawings, I have indicated generally at 5 the neck structure of a stringed musical instrument in accordance with my invention. The neck structure 5 includes a neck 6, one end I of which is conventionally formed and attached to the neck block 8 of the body 9 of the instrument. The other end of the neck 6 is formed to establish a head In disposed at an angle to the neck 6.

The neck 6 has on its upper surface a finger board II and the head I!) is finished as by the layer l2. Each of the strings I3 is attached at one end to the body 9 of the instrument and is supported in spaced relation to the finger board II and to the other strings by a stringnut or support M. The other end of each string I3 is connected to the part of a rotatable key [5 by which it may be suitablytensioned or released.

Because of the angular relation between the head [0 and the neck 6, and because of the tension on the strings, the neck 6 is apt to become bowed and the usefulness of the instrument seriously impaired.

Such bowing of the neck may be overcome, in accordance with my invention, by providing the upper surfaces of the neck structure with a channel l6 extending adjacent the neck end I forwardly into the head l0. Adjacent the junction between the neck 6 and head I0, I widen the channel 16 to establish a, nut accommodating chamber l1. 1

I anchor a member I8 in the channel l6. This may be easily effected by forming the member l8 with a downturned end I9 which may be suitably anchored by driving it into the neck end I. The other end of the member I8 is threaded as at 20 and extends into the head l0. Because of the angular relation between the neck 6 and the head Ill, the member I8 is preferably bent so that the threaded end 20 extends slightly downwardly.

tween the nut 2| and the head in; By this struc ture, by rotating the nut 2| to advance it towards the head Ill, corrective stress is applied; at opposite ends of the neck 6 and towards those ends so that any bowing of the'neck G'may be corrected.

In practice, I prefer to provide the neck 6 adjacent its head end, with a channel straddling guard 25, anchored to the neck 6 as at 2B.v to eliminate any possibility of the member I8 itself bor n as t e eat?! ismtaied. and ng in the fin e bo rd; and Feed n s pa a e it from the neck'ii.

nr t q i e errovis e a s t-s a Opening 21- in cOmrnunicatiQrLWith the chamberi'! by terminat n the ea er a d H short of layer I2 on the head lll This opening is normally closed by the string nut or support M wh h isz el ti h ly-s ated t e w en the n rum -is trun When e n u en is unstrung, the string nut lgrnay be removed to e mi t u Zlrtab retate by mean .q a wrench, not shown. I

A w be a pa ent Hem the d s h neck 6 tapers towards the head 10 and is, accordingly, more likely to bow adjacent the head. For that reason-Adorn; the chamber l'l' so that only at its front end, that-is, under the open-, elt it suf icientl lat rhan -the nut 2| t ac m od t h wren ha -thi on tr tion l m able: t eti zemean r Prov in a o ec v st es at heaee d i the. n ck w o em vin -slimmestweed s a preciab e weaken he na s in is s me in w i h in mostlikely-to occur. 7

N k 2 .et m vv o r g music ns r me t ee o a qe with ie mie a l dapte to q eet t bew gof he ne k- Not. nl a e th co e tivestr sees e iedat t x em ies-9 at ast. o he neck in ich bowing occurs, but also adjustments 'may l be a y q a he s mati i ei h ch i m. is wholly concealed sothat theappearance of. the instrument is not interiered withjand then-rechanism. itself is inexpensive to ,nianufacture and i easily installed. i

W a I h f e aim. Letters Patent is:

'1. A neck structure for astringed musical instrunient, said structure comprising a neck; one end of which is attached to one end of the body of the instrumentto the opposite end of which body the strings are connected, and an angular-1y and d si e e ure. y

upper surface extending from adjacent the body attaching end of said neck into said head, a thrust member transversely anchored in said channel adjacent the junction of said neck and head a finger board closing said channel and terminatging short of said head to provide a slot-shaped opening in communication with said channel adjacent said thrust member, a transverse string support positioned in said opening to establish a closure therefor, said support being held in place by the strings when the instrument is strung, extendable means anchored to said neck in said channel adjacent its body attaching end and in said head, said means including a rotatable member bearing against said thrust member and accessi ble through said opening when said support is removed so that'should said neck become bowed by string. tension a corrective stress may be applied substantially at and towards its opposite ends by r tatin a membe t x nd sa ean neck structure for a stringed musical in,-. strurnent, said structure comprising aineck, one end of which is attachedlto one end of the body of theinstrument tov theopposite end ofwhich body t st are enn ctd nd n neu ar y di posed head on the other endoi said neckufor the rotatable-pegsto, which. the strings are connected and-by which they are tensioned, saidstructure having; ailongitudinalchannel in its upper surface ex end n fr d ac nt he may atta h g end o said ne k'mt said h ad and hei aw ened est blish ha be'rad ace llt 'po o s of:

disposed head on the otherend-of said1neck -for structure having a longitudinal channelin its sa dn ck nd h a a mem anc o edn aid channe ad c n s hwy-a achin nd ndext ndi m g ai ead, the h m e ririgend of said member being'threadedfmeans anchored to the upp r u fate Qia d h d 0n oppo ite sid of said c nne and-i l ding a ange e d n into saidchamberto provide a transverse-shoud rsu ta t a ya the uncti n o a d h dand neck and beinglapertured-freely to receive said. member, and anut threaded on said member and. disposed between its anchored. end and saidshoule derso. that should .said neck. become. bowed by string t qna cqr e tiv s re sfm v e-a p ied substantially at and towards its oppositeends by d en in ai n t agai s a dshoulder;

'3. Thejneck structureot cIaimJZ and atranse versely disposed retaining member spanning the channel adjacent the head end of. the-neck and on ec ed ir etly th ret L The ne ktr etur i l mz in hi e memb r s a ro a in u ed endane chore'd. in the eck nd a ingt hr aded e d. disposed downwardly at. an angle. ,to..i ts interme.- diateposition.

' S ROMB RG; 

